I recently upgraded my memory on my old PC. I was wondering whether somebody could point me to a comprehensive guide my being able to access all 4GB of ram on a 32-bit system or, if possible, just tell me here and how to check.

I believe that Linux is fairly good about seeing all 4 gigs of ram on 32 bit, however you would gain from installing 64 big. 4 gigs is the theoretical limit for 32 bits. You can get higher memory support on 32 bit, but it is a hack.

64 bit also includes access to more registers and better handling of some computationally intense processes. Given development focus and performance enhancements, I would simply use 64 bit if you can._________________First things first, but not necessarily in that order.

Apologies if I take a while to respond. I'm currently working on the dematerialization circuit for my blue box.

This means you can see about 3.6G of your 4G memory. The rest has vanished under the memory mapped IO space.

You may be able to see the rest if you use HIMEM64G, however this is a hack, as the Doctor said.
You still only have a 4G address space but now you have several of them.

The Physical Address Space Extension (PAE) is enabled, so you get 36 bit in the physical addresses but any process still has 32 bit pointers.
Its paging by another name ... think expanded memory in early PCs.

I don't know if your system will map the RAM hidden under the memory mapped IO space to somewhere above 4G. Thats required to be able to use it.
Its also required to boot with HIMEM64G set.

Keep your old kernel handy in case it doesn't work._________________Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

This means you can see about 3.6G of your 4G memory. The rest has vanished under the memory mapped IO space.

You may be able to see the rest if you use HIMEM64G, however this is a hack, as the Doctor said.
You still only have a 4G address space but now you have several of them.

The Physical Address Space Extension (PAE) is enabled, so you get 36 bit in the physical addresses but any process still has 32 bit pointers.
Its paging by another name ... think expanded memory in early PCs.

I don't know if your system will map the RAM hidden under the memory mapped IO space to somewhere above 4G. Thats required to be able to use it.
Its also required to boot with HIMEM64G set.

Keep your old kernel handy in case it doesn't work.

I see... I tried doing this and the kernel booted fine. Xorg didn't start, but I imagine that I had to reinstall the nvidia drivers. It didn't seem to make a difference according to free -h.

Some BIOSes have a memory remap option to move the memory from the PCI address space to the area above that. Google seems to indicate that Dell specifies 2 GB maximum memory for the Dimension 8300, which could mean that your BIOS is lacking this function.